While playing on a lan server with a housemate (they are host). my internet cut out (told me I was disconnected by server) while I was in the end and they were in the overworld. I used save and quit to leave while disconnected, and after reconnecting and relogging, I was expecting to appear back where I was prior to disconnecting. But instead was loaded in with 0 levels, none of my tools or armour, only with the starting map, as if I was a brand new player, it had even reset from member to visitor. It wouldn't be too bad, but it is a survival only world so we can get achievements, and I had to grind for hours ** for all of my tools and enchantments (full netherite, with mac enchantments). It had even reset the data for my enderchest.

Any help would be grately appreciated.